mesa: Add an attribute for conditions to turn off threading.

The threading for GL core is in place, but there are so few applications
actually using a core GL context that it would be nice to extend support
back.  However, some of the features of compat GL (particularly user
vertex arrays) would be so expensive to track state for that we want to be
able to disable threading when we discover that the app is using them.

Acked-by: Timothy Arceri <[email protected]>
Acked-by: Marek Olšák <[email protected]>
Tested-by: Dieter Nützel <[email protected]>
Tested-by: Mike Lothian <[email protected]>

3 files changed, 15 insertions, 1 deletions

diff --git a/src/mapi/glapi/gen/gl_API.dtd b/src/mapi/glapi/gen/gl_API.dtd
index 133bc042aa9..dc4a199bb99 100644
--- a/src/mapi/glapi/gen/gl_API.dtd
+++ b/src/mapi/glapi/gen/gl_API.dtd
@@ -39,7 +39,8 @@
                    deprecated          CDATA   "none"
                    exec                NMTOKEN #IMPLIED
                    desktop             (true | false) "true"
-                   marshal             NMTOKEN #IMPLIED>
+                   marshal             NMTOKEN #IMPLIED
+                   marshal_fail        CDATA #IMPLIED>
 <!ATTLIST size     name                NMTOKEN #REQUIRED
                    count               NMTOKEN #IMPLIED
                    mode                (get | set) "set">
@@ -129,6 +130,10 @@ param:
         generated but a custom implementation will be present in marshal.c.
         If "draw", it will follow the "async" rules except that "indices" are
         ignored (since they may come from a VBO).
+     marshal_fail - an expression that, if it evaluates true, causes glthread
+        to finish and tear down before the Mesa implementation is called
+        directly.  Used to disable glthread for GL compatibility interactions
+        that we don't want to track state for.
 
 glx:
      rop - Opcode value for "render" commands
diff --git a/src/mapi/glapi/gen/gl_marshal.py b/src/mapi/glapi/gen/gl_marshal.py
index 1a633435001..a50d773e27e 100644
--- a/src/mapi/glapi/gen/gl_marshal.py
+++ b/src/mapi/glapi/gen/gl_marshal.py
@@ -236,6 +236,14 @@ class PrintCode(gl_XML.gl_print_base):
 
             self.validate_count_or_return(func)
 
+            if func.marshal_fail:
+                out('if ({0}) {{'.format(func.marshal_fail))
+                with indent():
+                    out('_mesa_glthread_destroy(ctx);')
+                    self.print_sync_dispatch(func)
+                    out('return;')
+                out('}')
+
             out('if (cmd_size <= MARSHAL_MAX_CMD_SIZE) {')
             with indent():
                 self.print_async_dispatch(func)
diff --git a/src/mapi/glapi/gen/marshal_XML.py b/src/mapi/glapi/gen/marshal_XML.py
index d56e4dda4af..80f7f542e43 100644
--- a/src/mapi/glapi/gen/marshal_XML.py
+++ b/src/mapi/glapi/gen/marshal_XML.py
@@ -58,6 +58,7 @@ class marshal_function(gl_XML.gl_function):
 
         # Store the "marshal" attribute, if present.
         self.marshal = element.get('marshal')
+        self.marshal_fail = element.get('marshal_fail')
 
     def marshal_flavor(self):
         """Find out how this function should be marshalled between